Automatic electric dishwashers are well known for household use. Such dishwashers have come to be an accepted part of modern, fully-equipped kitchens. As these dishwashers are continually improved upon and perfected, more and more design characteristics become important. Currently, dishwasher manufacturers are striving to make their automatic electric dishwashers operate as quietly as possible. It is to this end that the present invention is directed.
Contemporary, automatic, electric dishwashers include a tub which defines a wash chamber, which tub has a side opening and door pivotally attached to close the side opening, and a pump-motor compartment therebelow. There is, generally, a plurality of superposed dishracks mounted for movement through the opening and a spray means located within the tub to distribute washing liquid over dishes placed in the receiving racks. The tub is provided with an outlet which is in fluid flow relationship with the inlet of the pump-motor arrangement so that liquid may be continuously cycled from the pump outlet through the spray means, to the wash chamber, and returned through the outlet of the tub to the pump inlet.
Normally, the connection between the tub outlet and the pump inlet is steel or other similar durable material. Recently, however, it has been found that by providing a flexible, resilient connection means, made of rubber or some other polymeric resinous material, significant dampening of vibrations from the pump-motor arrangement through the connection to the tub can be accomplished.
However, with such a connection, there is an open sound channel from the pump inlet through the connection means into the tub. The tub, in turn, tends to act as a resonating board to amplify the sound from the pump assembly and transmit it throughout the kitchen area.
Prior art attempts at dampening the sound emanating from a dishwasher pump assembly include U.S. Pat. No. 3,398,866, which provided the pump with a sound-dampening impeller. Another attempt at providing a sound-dampening pump is exemplified in U.S. Pat. No. 2,973,716.
Both of these prior references indicate that reducing the sound emanating from an automatic electric dishwasher has been of concern. However, neither of them suggests the idea of providing a flexible trap connection between the tub drain and the pump inlet and providing a tongue member located therein, as will be more fully described hereinafter.
In a similar vein, structure having a likeness to the present invention is shown in U.S. Pat. No. 1,721,117, wherein it is suggested that a tongue member be enclosed within a T-coupling to serve as a flow divider. However, U.S. Pat. No. 1,721,117 does not suggest the use of a tongue member in combination with a water trap to effect sound dampening.
The invention described herein is an inexpensive, readily-constructed, and easily-maintained liquid trap connection which is effective in dampening sound, emanating from the pump-motor arrangement in a dishwasher.